公开(公告)号：US4064217A

公开(公告)日：1977-12-20

申请号：US728215

申请日：1976-09-30

申请人： George J. Hartman ,  Michael G. Darland

发明人： George J. Hartman ,  Michael G. Darland

IPC分类号： C01D5/00 ,  C01F7/06

CPC分类号： C01F7/0686 ,  C01D5/008

摘要： An improvement in the process for recovering aluminum from alunite ore disclosed in U.S. Pat. Nos. 3,890,425 and 3,890,426, the improvement being in the recovery of potassium sulfate by crystallization from the leaching solution resulting from potassium hydroxide leaching of the roasted ore, the improvement consisting of adding potassium hydroxide to the concentrated leach liquor prior to crystallization to increase the concentration of the potassium ion so that increased recoveries of potassium sulfate are obtained at a given temperature over those obtained when this procedure is not used. By this procedure a yield is obtained at a temperature below that which is required to obtain the same yield when potassium hydroxide is not used so that the high temperatures formerly necessary to hold enough potassium sulfate in solution for an economic crystallization are avoided. The improvement is particularly adapted to the process of the patents using potassium hydroxide as the leaching agent and in which the mother liquor is recycled to the leach as potassium hydroxide in an amount up to that required for the leaching step can be added in the crystallization step so that the potassium hydroxide serves both as a crystallization aid and as a leachant.

摘要翻译： 美国专利中公开的从铝酸钙矿中回收铝的方法的改进。 编号3,890,425和3,890,426，其改进在于通过从焙烧矿石的氢氧化钾浸出得到的浸出溶液中结晶回收硫酸钾，其改进包括在结晶之前向浓缩浸出液中加入氢氧化钾以提高浓度 的钾离子，使得在给定温度下获得的硫酸钾的回收率提高超过不使用该方法时获得的那些。 通过该方法，在低于当不使用氢氧化钾时获得相同产率所需的温度下获得的产率是可以获得的，因此避免了先前在用于经济结晶的溶液中保持足够的硫酸钾所需的高温。 该改进特别适用于使用氢氧化钾作为浸出剂的专利的方法，并且其中母液再循环至浸出液中，其中氢氧化钾的量可以达到浸出步骤所需的量，可以在结晶步骤中加入 使得氢氧化钾既用作结晶助剂又用作浸出剂。